阅读下面材料，在空白处填入适当的内容或括号内单词正确形式。
Amy: Sarah, how have your two sons been doing at school recently?
Sarah: Don’t ask! Peter never starts it while Sam never stops (study).
Amy: You’re joking! I hear that Jason is likely ____ (become) the top student after exams this year．
Sarah: Yes, so his teachers say. He has been working very hard at his books every evening for months end recently. Actually, he is making __
__(prepare)for Peking University.
Amy: Great. Maybe he’ll become a university professor in the future.
Sarah: Maybe. But sometimes I wish he'd go out and enjoy (he)for a change.
Amy: Yes. What about the (young) one?
Sarah: Well, he has the ability, but he (be) always busy.
Amy: What is he busy with?
Sarah: I really mean when I say he is always busy is that he doesn’t consider study as a top priority.
Amy: I am (terrible) sorry to hear that. But kids can always find reasonable excuse to avoid studying.
Sarah: Yes. But he is really crazy about variety of sports, such as football and basketball.
Amy: Perhaps he can make his fortune at football in the future. People can make a large amount of money from sports now.
Sarah: I hope so.
It seemed that the water led to cholera．John Snow looked into the source of the water for these two streets．He found that it came from the river, had been polluted by the dirty water from London．Immediately John Snow told the astonished people in Broad Street to remove the handle from the water pump so it could not be used．Soon the disease began to slow
．
John Snow had shown that cholera was spread by germs and not in a cloud of gas．___addition, he found two other deaths in another part of London that were concerned with the Broad Street outbreak．A woman, who had moved away from Broad Street, liked the water so much that she had had it delivered from the pump to her house every day．
Technological developments have also played their part ______ keeping Valentine’s Day relevant in the 21st century. Valentine’s ecards have been very popular in recent years.
Now，Valentine’s Day is celebrated in many countries around the world. However, the traditions often differ from place to place.
In Japan，for example，it is normal _______the woman to send chocolates to the man, ___
___in South Korea April 14th is known as “Black Day” and is when the unfortunate men who received nothing on Valentine’s Day gather to eat noodles and show sympathy for each other.
_______is believed that he tried to find comfort from his imprisonment by writing love poems to his wife.
Nobody knows exactly ________St.Valentine was，although some historians suggest he was ___
___Roman killed in the third century AD by a Roman Emperor.